客气

She is the pick of politeness.

They say so out of politeness.

They use much ceremony with each other.

He treated us politely.

You'll get the rough side of my tongue if you are cheeky again.

with a great/good deal of ceremony

refuse bluntly

greet (sb) politely

polite remarks

They exchanged a few remarks of courtesy.

After a few words of courtesy, he accepted the present.

［said to one's guest］ Please don't stand on ceremony. / Make yourself at home. / ［said to one's host］ Please don't bother.